Lead aVR is an electrocardiographic lead that is frequently ignored [1, 2]. Many clinicians consider lead aVR as a not useful electrocardiogram one. Instead of this, we report a patient that was resuscitated from a ventricular fibrillation and presented with ST-elevation in lead aVr (Figures 1 and 2) and right bundle brunch block. The patient was immediately transferred to the cath lab and a left main coronary artery occlusion (LMCA) was visualized [3]. In this emergency scenario the patient had another cardiac arrest in pulseless electric activity and we proceeded with percutaneous revascularization of the LMCA (Figure 3). The patient returned to spontaneous circulation and after 14 days was dispatched from hospital without neurologic sequelae. The rapid diagnosis of such events is critical to guiding early intervention and appropriate disposition in many patients with ACS. Electrocardiography is an appropriate bedside tool used in the ED to make a rapid diagnosis of ACS especially using the aVr lead, allowing physicians to select appropriate therapy and to predict potential cardiovascular complications.